Thoughts on measuring one way speed of light

The One-Way Speed of Light Problem is a fundamental issue in physics and philosophy of science concerning whether the speed of light in one direction (e.g., from point A to point B) can be measured independently of the round-trip (two-way) speed of light. The problem arises due to the following considerations:

Problem Statement:

1. Definition Dependence: The speed of light in a single direction (one-way speed) cannot be directly measured without assumptions about the synchronization of clocks at different locations.
2. Einstein Synchronization: Special Relativity assumes that light travels at the same speed in all directions, but this assumption relies on synchronizing clocks at different locations using light signals, creating a circular dependency.
3. Measurement Challenge: Any attempt to measure the one-way speed of light requires synchronized clocks, but synchronization methods themselves depend on assumptions about the speed of light.
4. Conventionality Thesis: Since we can only measure the round-trip speed of light (which is always $c = 299,792,458$ m/s in a vacuum), different synchronization conventions might allow different values for the one-way speed without contradicting experimental result.

 Existing Solutions proposed in literature as on 20th February, 2025 compiled by ChatGPT:

The One-Way Speed of Light Problem remains unresolved in physics because it is fundamentally tied to the issue of clock synchronization. However, several approaches attempt to address or work around this problem. Here are some possible solutions or interpretations:

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1. Einstein Synchronization (Conventionality of Simultaneity)

• Solution: Assume the one-way speed of light is equal to the two-way speed of light ($c$). This is the standard approach in special relativity.
• Justification: This assumption is built into Einstein’s 1905 postulates of special relativity and has been used successfully in physics.
• Limitation: It does not prove that the one-way speed is necessarily $c$, only that assuming so leads to a consistent framework.

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2. Alternative Synchronization Conventions

• Solution: Some argue that different synchronization schemes might allow the one-way speed of light to be different while keeping all experimental results consistent.
• Example: The Reichenbach Synchronization allows a non-standard synchronization where the speed of light in one direction can be anything from $c/2$ to infinity.
• Limitation: These alternative conventions do not change physical predictions; they only reinterpret simultaneity.

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3. Direct Measurement Attempts

• Solution: Various experimental setups have tried to measure the one-way speed of light directly.
• Example Attempts:
  • Using moving clocks (e.g., atomic clocks transported by aircraft).
  • Using GPS signals and synchronization with atomic clocks.
  • Asymmetries in astrophysical observations.
• Limitation: Every experiment so far either assumes clock synchronization or reduces to a two-way measurement.

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4. Philosophical and Theoretical Approaches

• Conventionalist View: The one-way speed of light is not a measurable physical quantity but a matter of convention.
• Realist View: Some theorists argue that an unknown physical effect might determine the actual one-way speed, but no such effect has been found.

---

5. New Physics Beyond Special Relativity

• Solution: If future physics (e.g., quantum gravity or new spacetime structures) provides a preferred frame of reference, it might allow direct measurement of the one-way speed.
• Example: Some quantum entanglement experiments suggest nonlocal correlations that might offer new ways to probe simultaneity.

 

Proposed Solution:

 What if we are bound by our thought processes? What if we were thinking a different direction altogether for a solution?

Let's try out some out of the box thinking.....

Does light only travel in a straight line? True

Does the medium it travels through is fixed...? Well, the answer is no. Space time continuum is known to bend under the influence of gravity and as such light bends around massive masses like black holes. This gives rise to phenomenons like gravitational lensing which modern physics is known to utilize to observe black holes in space.

 So, the idea is the medium itself bends but light keeps going in a straight line and we can measure the one way speed of light. Given that many physicists might of thought of this  solution there might be some drawbacks to this solution. So, if you are a budding physicists or a stalwart in the field and you bumped onto this article, it will be kind of you to explain the theoretical problems with this approach in the comments. If there are no such problems, feel free to suggest solutions to overcome drawbacks performing this experiment in the comments.

 

A diagram providing a visual description of the solution:

 

If you are interested in solving this problem and want to get in touch feel free to drop a mail at subrotosarkar32@gmail.com

 

Django: Database Migration from sqlite to mariadb

 

Migrating Your Django Database from SQLite to MariaDB

Switching from SQLite to MariaDB in Django involves a few key steps: adding the new database, migrating data, and updating your settings. Follow this step-by-step guide to ensure a smooth transition.

---

1. Add the New Database to settings.py

First, update your settings.py file to include the new MariaDB database. Add the following entry under the DATABASES dictionary:

'new': {
    'ENGINE': 'django.db.backends.mysql',
    'NAME': 'your_database_name',
    'USER': 'your_database_user',
    'PASSWORD': 'your_database_password',
    'HOST': 'localhost',  # Change if using a remote server
    'PORT': '3306',
}

After adding this, your DATABASES section should look something like this:

DATABASES = {
    'default': {
        'ENGINE': 'django.db.backends.sqlite3',
        'NAME': os.path.join(BASE_DIR, 'db.sqlite3'),
    },
    'new': {
        'ENGINE': 'django.db.backends.mysql',
        'NAME': 'your_database_name',
        'USER': 'your_database_user',
        'PASSWORD': 'your_database_password',
        'HOST': 'your_database_host',
        'PORT': '3306',
    }
}

Note: Ensure that you have installed the MariaDB (or MySQL) client on your machine before proceeding.

---

2. Migrate Database Schema to the New Database

Run the following command to create tables in your new MariaDB database:

python manage.py migrate --database=new

Important: If you have accidentally deleted the migrations folder, recreate it by running python manage.py makemigrations before proceeding.

---

3. Transfer Data to the New Database (Optional)

If you want to migrate existing data from SQLite to MariaDB, follow these steps:

a) Clear the New Database

Ensure the new database is empty before transferring data:

python manage.py flush --database=new

b) Export Data from SQLite

Dump the data from your current SQLite database into a JSON file:

python -Xutf8 manage.py dumpdata --exclude auth.permission --exclude contenttypes --output data.json

c) Load Data into MariaDB

Now, import the data into your new database:

python manage.py loaddata data.json --database=new

---

4. Switch to the New Database

Once the migration is complete, update settings.py to make MariaDB the default database. Remove the old SQLite entry and rename new to default:

DATABASES = {
    'default': {
        'ENGINE': 'django.db.backends.mysql',
        'NAME': 'your_database_name',
        'USER': 'your_database_user',
        'PASSWORD': 'your_database_password',
        'HOST': 'your_database_host',
        'PORT': '3306',
    }
}

---

5. Final Check

Restart your Django server and verify that your application is using the new MariaDB database.

python manage.py runserver

If everything is working as expected, you have successfully migrated from SQLite to MariaDB!

Need Help? Feel free to ask any questions in the comments, and we’ll try to address them.

Home Automation: Using Arduino Uno & ESP8266(Blynk app)

 Hardware required:

    1>Arduino UNO(r3)
    2>ESP8266-01 wifi module
    3>4 channel relay
    4>Male to female jumper wires
    5>Adaptor(output:12V/1Amp) 
You could check out amazon or if you live near kolkata Chadni market is where you can get these for really cheap

Software required:

    1>Arduino IDE, Link:https://www.arduino.cc/en/Main/Software
    2>Blynk library for Arduino, Link:https://github.com/blynkkk/blynk-library/releases/tag/v0.5.4
    3>Project files provided
    4>Blynk App on Android/iOS, Link:https://play.google.com/store/apps/details?id=cc.blynk


Now,
Steps to make the project:

1. make connections as in connect2.png
2. power up using pc via usb
3. open up arduino ide
4. Load from File->Examples->Bare Minimum
5. Verify and upload the file
6. Open serial monitor
7. Set NL&CR and baud rate to 115200(this is the default rate)
8. Now give command ("AT") it should return ("OK") if you don't get anything check other baud rates or else you need to flash the firmware.
9. Now give command ("AT+CWMODE=1) it set the chip in station mode(client)
10. Give command("AT+UART_DEF=9600,8,1,0,0") it will change baud rate to 9600
11. change baud ratee in serial monitor to 9600
12. Now give command("AT+CWLAP") and see if your home wifi gets listed, if not then turn on your home wifi or try to move closer to your home wifi.
13. We will try to connect to home wifi network.
14. Give command ("AT+CWJAP="home_wifi","password") and it will return text if it gets connected, also you could check using your home wifi's page
15. Let's disconnect, give command("AT+CWQAP") it should return ("OK"). Now , that our wifi module is working let us get into the work, make connections as in final.png
16. Setup blynk app on your andriod/iOS device.
17. Load the code provided making required changes as mentioned in comments to the arduino borad.(Change the blynk Auth token,wifi name/ssid,password with your own)
18. Now that your code has been uploaded you can put the device with live circuits, but be careful not to hurt yourself, also you could power the arduino using an adapter.

Final Connections:




Project files download:

Here is github linkfor the project: https://github.com/SubrataSarkar32/home-automation

Sara - A virtual assisstant made in python

Have you ever wondered about building your own virtual assistant? Off course who might have not, specifically something like Jarvis. Now you can too with Python and other languages with their rich libraries at your disposal.Here is my small glimpse of what can be done in Python. I have made my assistant(Sara) with very limited features to start off with. Features would be kept on adding and your help would be appreciated always as it is licensed under GPLv2. Also you can tinker around with it to make your own assistant styled according to you as it is under GPLv2.
Hope you like it.
It is available at https://github.com/SubrataSarkar32/sara
Here is a vedio below:

pdecrypt(Python:Simple Caesar Cipher)

Ever felt the need to encrypt text data. Now do it easily using pdencrypt(works on simple caesar cipher).This is a python program. After creating a file you would like to keep the python with you so that no one gets clue.Can be considered public domain work.You responsible for using the software properly You take liability of storing your own data and protecting it Programmer is not responsible for mistakes on part of user. If you have any suggestions feel free to coment.
Sorry small update for typo erors:
import string
name=raw_input('Enter file name: ')
def entangle(t):
    key=13
    lock=string.printable
    ret=''
    for wor in t:
        po=lock.find(wor)
        if po+key>=len(lock):
            po=((po+key)-(len(lock)-1))-1
        else:
            po+=key
        ret+=lock[po]
    return ret
def disentangle(t):
    key=13
    lock=string.printable
    ret=''
    for wor in t:
        po=lock.find(wor)
        if po-key<0:
            po=len(lock)+(po-key)
        else:
            po-=key
        ret+=lock[po]
    return ret

def read(name):
    file1=open(name,'r+')
    op=file1.readlines()
    for obj in op:
        obj=disentangle(obj)
        print obj
    file1.close()
def write(name):
    file1=open(name,'r+')
    t=raw_input('Enter ;')
    t=entangle(t)
    prev=file1.read()
    wr=prev+t+'\n'
    file1.close()
    file1=open(name,'w+')
    file1.write(wr)
    file1.close()
def main(name):
    file1=open(name,'r+')
    keyi=file1.readline()
    file1.close()
    key=raw_input('Enter your key: ')
    if key==disentangle(keyi[:-1]):
        while True:
            choi=raw_input('choice:')
            if choi=='1':
                read(name)
            elif choi=='2':
                write(name)
            elif choi=='3':
                break
            else:
                print 'invalid input'
                print 'program quitting'
                file1=open(name,'r+')
                prev=file1.read()
                wr=prev+'\n'
                file1.close()
                file1=open(entangle(name)+'.tri','w+')
                file1.write(wr)
                file1.close()
                file1=open(name,'w+')
                file1.write(name)
                file1.close()
    else:
        print 'Warning!! do not interfere encrypted txt'
        file1=open(name,'r+')
        prev=file1.read()
        wr=prev+'\n'+entangle('Warning!Someone tried to access your file')+'\n'
        file1.close()
def run():
    import os
    if os.path.isfile(name):
        main(name)
    else:
        file1=open(name,'w+')
        print 'This is important!!'
        print 'Your key is being set.'
        print 'You must remember this else your information stored is doomed'
        import random
        k=random.randint(10,len(string.printable)-1)
        print 'Your key is ',k
        stor=entangle(str(k))+'\n'
        file1.write(stor)
        file1.close()
        main(name)
run()

Facebook+Python=Awesome

Do you like python? Do you use facebook?

If the answer is yes why not use facebook via python.

Below is the code to use facebook via python .This program has been inspired by http://www.geeksforgeeks.org/send-message-to-fb-friend-using-python
 Disclaimer of Warranties and Limitation of Liability.
a.Unless otherwise separately undertaken by the author, to the extent possible, the author offers the Licensed Material as-is and as-available, and makes no representations or warranties of any kind concerning the Licensed Material, whether express, implied, statutory, or other. This includes, without limitation, warranties of title, merchantability, fitness for a particular purpose, non-infringement, absence of latent or other defects, accuracy, or the presence or absence of errors, whether or not known or discoverable. Where disclaimers of warranties are not allowed in full or in part, this disclaimer may not apply to You.
b.The disclaimer of warranties and limitation of liability provided above shall be interpreted in a manner that, to the extent possible, most closely approximates an absolute disclaimer and waiver of all liability.
Check out fbchat's policies before continuing.
# This code to be considered under GPLv3.Use it under your responsibility.
Code:
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
#Please use it carefully.Ensure loging out by using a browser
#Required dependencies:
#   requests
#   lxml
#   beautifulsoup4
#   fbchat
def main():
    '''main function: initiation of fbchat and login'''
    import fbchat
    from getpass import getpass
    username = str(raw_input("Username: "))
    client = fbchat.Client(username, getpass())
    '''
    #For sendig same message to specific number of clients
    no_of_friends = int(raw_input("Number of friends: "))
    for i in xrange(no_of_friends):
        name = str(raw_input("Name: "))
        friends = client.getUsers(name)  # return a list of names
        friend = friends[0]
        msg = str(raw_input("Message: "))
        ask = 'O'
        while ask.upper()!='Y' and ask.upper()!='N':
            ask = raw_input('Are you sure about sending this message to'+friend+'(Y/N):')
            if ask.upper()=='Y':
                sent = client.send(friend.uid, msg)
                if sent:
                    print("Message sent successfully!")
            elif ask.upper()=='N':
                print("Message was not sent .")'''
    def choicefrnd(friends):
        '''choose freind from list'''
        try:
             chno=input('Enter index of friend: ')
             friend = friends[chno-1]
             return friend
         except:
             print 'Please give index number as printed above from 1 to n'
             choicefrnd()
    def talk():
        '''talk with friends. Contains main loop and sub loops'''
        ch='y'
        while ch=='y':   
            name = str(raw_input("Name: "))
            friends = client.getUsers(name)  # return a list of names
            for i in xrange(len(friends)):
                print str(i+1)+str(friend[i])
            if len(friends)>=1:
                friend=choicefrnd(friends)
                msg = str(raw_input("Message: "))
                ask = 'O'
                while ask.upper()!='Q':
                   
                    ask = raw_input('Are you sure about sending this message to'+friend+'(Y/N):')
                    if ask.upper()=='Y':
                        sent = client.send(friend.uid, msg)
                        if sent:
                            print("Message sent successfully!")
                    elif ask.upper()=='N':
                        print("Message was not sent .")
                    elif ask.upper()=='Q':
                        break
                    else:
                        print 'Could not decipher your answer.'
                    print 'Press q to quit chatting this friend'
            else:
                pass           
        else:
            pass
        talk()
        client.logout()
main()

pyhinavrophonetic

Check out pyhinavrophonetic a tool to convert english phonetic to hindi.It is a python module.
At: http://pypi.python.org/pypi/pyhinavrophonetic